On the 'why spacers' issue ...
The appearance to a third person may not be much difference.
I put spacers on both my 570, and my 12C (but ordered mine from Thorney)
One definite advantage: You can clean your calipers !
Customer sent me some pics of wheel spacers installed on a 570s, that we supplied him.
These spacers are super light and all the excess material has been machine out.
Is there anything do "install" on these or do they simply fit on the hub and you bolt up the wheel (like other spacers Ive used)? Its not clear in the photos if there is anything else to do other then place them.